Low cost oil/grease separator

ABSTRACT

A container for receiving and holding effluent water containing oil/grease to be removed has sectional covers. A main sectional cover supports a partially immersed rotatable disk; a drive on the main sectional cover rotates the disk; a trough on the main sectional cover straddles the disk; and a blade on the trough scrapes a side of the disk, to direct oil and grease from the disk along the scraper blade along the trough for collection in a storage container. Efficiencies of construction of the sectional covers, disk and a sensor probe are disclosed.

BACKGROUND OF THE INVENTION

This invention relates to a low cost assembly for the removal andrecovery of oil, grease and solid wastes found in drains or effluentdischarge of restaurants, food processing, or like facilities,industrial plants, maintenance facilities, or other circumstancesinvolving mixtures of oil, grease and solid waste material to berecovered or removed. This application has subject matter similar to thedisclosure of U.S. patent application Ser. No. 10/161,814, filed Jun. 4,2002, the entire disclosure of which is hereby incorporated herein byreference.

Oil, grease and solid waste contaminant removal or recovery systems arewell known in the prior art. Over the past thirty years there has been asteady move towards requiring food handling facilities to have systemsfor servicing kitchen grease and solid waste bearing water flows. Sewersystem lines can become clogged from the oil and grease waste materials(hereinafter referred to as “oil/grease”) put into the sewer system fromfood handling facilities. This has led more and more sewer authoritiesto implement fats, oils and grease control programs. These programsregulate food handling facilities and the manner in which they processoil, grease and solid waste material. The object of many of theseprograms is to ensure that food handling facilities remove as much ofthe oil and grease as possible from the effluent flow, thereby releasingonly grey water to the sewer system.

One method recognized in the prior art of accomplishing such removal isthe use of a container including one or more rotating disks formed of aplastic or like applicable material to which oil and grease contaminantsare attracted. Typically, the rotation of the disk is in an at leastpartially immersed condition, which allows the oil to cling to one orboth sides of the disk so that contaminants are removed from the body ofwater upon rotation of the disk. Scrapers are typically used to forcethe oil contaminants from the opposite sides of the disk and channelsuch contaminants to a collection or disposal storage unit.

U.S. Pat. No. 5,133,881 to Miller et al. is representative of such oiland grease removal systems containing one or more rotating disks. TheMiller et al. patent discloses an oil/grease removal assembly whichremoves such contaminants from the surface of the body of water andincludes a rotatable disk made of plastic or other material to whichsuch oil contaminants have an affinity so they adhere to the disk. Thedisk is disposed in cooperative relation to an elongated trough havingscraper blades for engaging the opposite sides of the disk for theremoval of the oil contaminants therefrom with the trough disposed andstructured to direct such oil contaminants away from the disk and thebody of water via the trough to a storage container. The disclosure ofthis patent, issued to B. Glenn Miller and William C. Batten andassigned to Thermaco, Inc. in Asheboro, N.C., is hereby incorporatedherein by reference.

The existing devices may be difficult to service and are very oftenpermanently installed at facility sites. Because many of the parts arecoated with oil and grease, servicing can be messy and time consuming.In addition, these systems tend to be expensive and represent asignificant capital investment. Accordingly, there is a need in the artfor an apparatus for separation of oil, grease and solid waste fromwastewater which is simple in design, low in cost and capable of beingserviced easily in the field because of the availability of low costreplaceable parts which are easily installed and do not requireextensive and costly repair.

SUMMARY OF THE INVENTION

The present invention fulfills one or more of these needs in the art byproviding a modular oil/grease removal assembly including a containerfor receiving and holding effluent water containing oil/grease to beremoved from the effluent water and having sectional covers. A mainsectional cover supports a rotatable disk in a partially immersedposition within the body of effluent water and in contact with theoil/grease. A drive is mounted on the main sectional cover in drivingengagement to provide rotation of the disk when the drive is engaged. Atrough is mounted on the main sectional cover in engaging relation toopposite sides of the rotatable disk, and a scraper blade is mounted onthe trough so that the scraper blade extends from the trough intosliding engagement with a side of the disk. The disk, scraper blade andtrough are cooperatively disposed and structured to direct oil andgrease from the disk along the scraper blade along the trough forcollection in a storage container.

In one embodiment the main sectional cover supports an electricalresistance heater that extends downwardly into the container so as tohave an operable portion of the heater at least partially immersedwithin the body of effluent water to cause the oil/grease to be inliquid form. The main sectional cover may also support electricalcontrols for selectively operating the drive and the heater. A firstshield preferably covers the rotating disk, trough and scraper blade,and a second shield covers the electrical controls. The first shield maybe provided with vent holes to permit the escape of vapors so as toreduce vapor condensation within the first shield. The first shield mayhave hinged portion covering at least portions of the rotating disk,trough and scraper blade, so that the hinged portion can be opened foraccess to clean and/or service the rotating disk, trough and scraperblade.

In one embodiment, a unitary shield covers the rotating disk, troughscraper blade, and the electrical controls. If a single shield is used,preferably, the shield has a partition to separate the rotating disk andtrough scraper blade from the electrical controls. The shield mayinclude front and rear sections meeting to form a barrel for a hinge forcovers for the rotating disk, trough scraper blade and electricalcontrols.

The electrical control may include a timer connected to the drive tocontrol the start and stop operation of the drive to permit a selectedduty cycle to remove grease at times when grease is likely to bepresent, and the second shield may have a hinged portion covering acontrol for the timer, permitting access to the timer without removal ofthe entire second shield.

The main sectional cover typically has two pair of opposite sides withone pair of opposite sides adapted to engage the container for supportof the main sectional cover by the container and the other pair ofopposite sides adapted to engage additional sectional covers. The sidesadapted to engage additional sections preferably have a flange extendingdownwardly and laterally so as to be positioned under a portion of anadditional section, with a further downard extension to providerigidity. The additional sectional cover is typically substantiallyrectangular with two opposite sides adapted to engage the container forsupport of the additional sectional cover by the container and one ofthe two other opposite sides adapted to engage and seal to the mainsection. The container typically has an inwardly turned upper flange, agasket on the flange, and clasps to hold the sectional covers to theflange and seal the covers to the flange by compression of the gasket.

The additional sectional cover may have four sides with three sidesadapted to engage the container for support of the additional sectionalcover by the container and the fourth side has an upper protrusion thathas a lower surface with a gasket so the upper protrusion engages andseals to an upper surface of the flange of the main sectional cover thatextends downwardly and laterally and a downward ear that engages thefurther downward extension of the main section.

Alternatively, the protrusion may be downward. In another alternative, apseudo hinge allows optional joining of sections.

The container typically has an inlet end, an outlet end and left andright sides, looking in the direction from the inlet to the outlet ends,and the sectional covers have first and second mounting edges so thatthey can be mounted to the container with a first mounting edge on theleft and a second mounting edge on the right or the second mounting edgeon the left and the first mounting edge on the right.

In one embodiment there are two or more main sectional covers and one ormore additional sectional covers between the main sectional covershaving opposite sides to engage the main sections. The opposite sides ofthe additional sectional cover each having upper and lower protrusionsspaced by a spacer of dimension so the upper protrusion engages an uppersurface of the flange of the main sectional cover that extendsdownwardly and laterally and the lower protrusion engages the furtherdownward extension. The upper protrusion may have a lower surface with agasket to seal with the flange of the main sectional cover that extendsdownwardly and laterally.

The apparatus may include an additional sectional cover, with thesectional covers configured to provide a hinged but severablerelationship between the sectional covers.

In one embodiment, the additional sectional cover has four sides withthree sides adapted to engage the container for support of theadditional sectional cover by the container. The fourth side has a lowerprotrusion and a gasket so the lower protrusion of the additionalsection abuts the further downward extension of the main sectional coverand the gasket engages and seals to the main sectional cover.

In one embodiment the disk includes two disk sheets separately formedand subsequently joined together. The two sheets preferably areidentical and each include a flat oleophilic surface and a surfacehaving a plurality of spaced peripheral lugs. The lugs of each sheet arepreferably odd in number so that upon turning the oleophilic surfacesaway from one another and joining the two sheets, the lugs of theopposing sheets may be interleaved to form a periphery for the disk withgaps between the lugs. The sheets may be joined by means selected fromthe group consisting of screwing, bolting, ultrasonic welding, vibrationwelding, other welding and adhering. The sheets may have bosses on thesame side as the lugs and the sheets are joined at the bosses. Thesheets are preferably injection molded plastic. A suitable plastic ispolypropylene. The drive may be a sprocket with flattened teeth toengage the lugs. The sheets preferably have central hole with asurrounding rim to form a bearing for an axle extending through thecentral hole.

The assembly may include a sensor module mounted to the main sectionalcover. The sensor module includes a probe extending downwardly withinthe body of effluent water to a depth normally below the oil/grease. Asensor in the probe provides electrical indications as to whether thesensor is in proximity to oil/grease or water. An alarm on the sensormodule to provide a human-recognizable indication if the sensor sensesthat the probe is in proximity to oil/grease rather than thenormally-present water. The sensor and alarm are typically electricaland are powered by a low voltage power supply to the sensor moduleseparate from power to the drive that rotates the disk. An electricalalarm output from the sensor module may be provided to enable electricalconnection to a remote monitoring apparatus to signal alarm conditionsto the remote monitoring apparatus, such as a SCADA monitoringapparatus. The probe is preferably a watertight cylindrical shaft, andthe sensor is positioned at a distal end of the cylindrical shaft andheld in place at the distal end by a spacer. The sensor module may alsoinclude a ready light indicating proper operation.

In one embodiment the container has an inlet end and a solids removalmodule positioned at the inlet end. The solids removal module may be astrainer. Alternatively, the solids removal module may include a hopperhaving an eductor at a lower portion of the hopper, a water inlet to theeductor to make a jet of water to remove contents of the hopper inproximity to the eductor and an outlet from the eductor to an outlet ofthe container. The hopper preferably includes a lower portion laterallyoffset from the eductor, so that excess solids do not block jet actionof the eductor.

The invention may also be considered as a method of assembly of amodular oil/grease removal assembly including installing a container forreceiving and holding effluent water containing oil/grease to be removedfrom the effluent water and having sectional covers; mounting a mainsectional cover supporting a rotatable disk for partial immersion withineffluent water in the container and in contact with the oil/grease, adrive in driving engagement to provide rotation of the disk when thedrive is engaged; a trough mounted on the main sectional cover inengaging relation to opposite sides of the rotatable disk; a scraperblade mounted on the trough so that the scraper blade extends from thetrough into sliding engagement with a side of the disk. The disk,scraper blade and trough are cooperatively disposed and structured todirect oil and grease from the disk along the scraper blade along thetrough for collection in a storage container. An electrical resistanceheater may be included that extends downwardly into the container so asto have an operable portion of the heater at least partially immersedwithin the body of effluent water to cause the oil/grease to be inliquid form. Electrical controls for selectively operating the drive andthe heater may also be on the main sectional cover. The method includesmounting additional sectional covers to cover the container, andinstalling a first shield to cover the rotating disk, trough and scraperblade and a second shield to cover the electrical controls.

The method may also be considered as including installing a containerfor receiving and holding effluent water containing oil/grease to beremoved from the effluent water and having sectional covers. The methodincludes mounting a main sectional cover that has two pair of oppositesides with one pair of opposite sides adapted to engage the containerfor support of the main sectional cover by the container and the otherpair of opposite sides having flanges extending downwardly and laterallywith a further extension downwardly to provide rigidity and thatsupports a rotatable disk for partial immersion within effluent water inthe container and in contact with the oil/grease, a drive in drivingengagement to provide rotation of the disk when the drive is engaged, atrough mounted on the main sectional cover in engaging relation toopposite sides of the rotatable disk, a scraper blade mounted on thetrough so that the scraper blade extends from the trough into slidingengagement with a side of the disk. The disk, scraper blade and troughare cooperatively disposed and structured to direct oil and grease fromthe disk along the scraper blade along the trough for collection in astorage container. An electrical resistance heater extends downwardlyinto the container so as to have an operable portion of the heater atleast partially immersed position within the body of effluent water tocause the oil/grease to be in liquid form. Electrical controls forselectively operate the drive and the heater. The method includesmounting additional sectional covers that have four sides with twoopposite sides engaging the container for support of the additionalsectional cover by the container and one of two opposite sides engagingthe main sectional cover.

When the container has an inwardly turned upper flange, and a gasket onthe flange, this method of assembly may include engaging clasps to holdthe sectional covers to the flange and seal the covers to the flange bycompression of the gasket.

The method may include installing two or more main sectional covers andone or more additional sectional covers between the main sections, theopposite sides of the additional sectional cover each having upper andlower protrusions spaced by a spacer by engaging the upper protrusion onan upper surface of the flange of the main sectional cover that extendsdownwardly and laterally and engaging the lower protrusion with thefurther downward extension. If the upper protrusion has a lower surfacewith a gasket the method may include sealing the upper protrusion withthe flange of the main sectional cover that extends laterally anddownwardly.

If the additional sectional cover has four sides with three sidesadapted to engage the container for support of the additional sectionalcover by the container and the fourth side has an upper or lowerprotrusion that has a lower surface with a gasket so the upperprotrusion, the method may include engaging and sealing the upperprotrusion to an upper surface of the flange of the main sectional coverthat extends downwardly and laterally and engaging a downward ear of theadditional sectional cover with the further downward extension of themain sectional cover.

The invention may also be considered as a method of assembly of amodular oil/grease removal assembly for receiving and holding effluentwater containing oil/grease to be removed from the effluent waterincluding identifying an inlet source of effluent water and a downstreamdrain for grey water, installing a container having an inlet, an outletand left and right sides looking in the direction from the inlet to theoutlet ends, installing a main sectional cover that supports thefunctional apparatus to remove oil/grease from water and dischargesoil/grease to one of the left and right sides of the container so thatthe discharge of oil/grease is convenient for servicing, and mountingadditional sectional covers to completely cover the container. Such amethod may also include refraining from mounting the main sectionalcover from a structurally feasible mounting that would have thedischarge of oil/grease be inconvenient for servicing.

The invention also may be considered as a method of making a disk for amodular oil/grease removal assembly including forming two disk sheetsseparately and subsequently joining the two disk sheets together to forma disk. Preferably, the two sheets are made identical and each include aflat oleophilic surface and a surface having a plurality of spacedperipheral lugs. Especially when the lugs of each sheet are odd innumber, the method includes turning the oleophilic surfaces away fromone another, interleaving the lugs of the opposing sheets, and joiningthe two sheets to form a periphery for the disk with gaps between thelugs. The sheets may be joined by means selected from the groupconsisting of screwing, bolting, ultrasonic welding, vibration welding,other welding and adhering. If the sheets have bosses on the same sideas the lugs, the method preferably includes joining the sheets at thebosses. Forming the sheets is preferably by injection molding plastic,particularly polypropylene. Forming preferably includes forming thesheets with a central hole with a surrounding rim to form a bearing andpassing an axle through the central hole.

The method may also include mounting a sensor module to the mainsectional cover including a probe extending downwardly within the bodyof effluent water to a depth normally below the oil/grease. A sensor inthe probe provides electrical indications as to whether the sensor is inproximity to oil/grease or water, and an alarm on the sensor moduleprovides a human-recognizable indication if the sensor senses that theprobe is in proximity to oil/grease rather than the normally-presentwater. Such a method preferably includes connecting a low voltage powersupply to the sensor module separate from the power to the functionalapparatus to remove oil/grease from water. It may also includeconnecting an electrical alarm output from the sensor module to a remotemonitoring apparatus to signal alarm conditions to the remote monitoringapparatus, such as a SCADA monitoring apparatus.

The method may also include positioning a solids removal module at theinlet end. The solids removal module may be a strainer. As analternative, the solids removal module may be a hopper having an eductorat a lower portion of the hopper, and the method includes includingconnecting a water inlet to the eductor to be available to make a jet ofwater to remove contents of the hopper in proximity to the eductor andconnecting an outlet from the eductor to an outlet of the container.

The invention also may be considered as a method of modifying a modularoil/grease removal assembly including removing one or more of thesectional covers, removing an installed solids removal strainer, andinstalling a hopper having an eductor at a lower portion of the hopper,and including connecting a water inlet to the eductor to be available tomake a jet of water to remove contents of the hopper in proximity to theeductor and connecting an outlet from the eductor to an outlet of thecontainer.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will be better understood by a reading of the DetailedDescription of the Preferred Embodiments along with a review of thedrawings, in which:

FIG. 1 is a perspective view of an embodiment of the invention;

FIG. 2 is a perspective view of the container with the shields removed;

FIG. 3 is a perspective view of the container with one of the additionalcover sections removed;

FIG. 4 is an enlarged perspective view of the mating of an additionalsectional cover with the main sectional cover;

FIG. 4A is a sectional view of two main sectional covers mated with afurther additional sectional cover;

FIG. 4B is a view of an alternate embodiment of the additional sectionalcover with a downward protrusion;

FIG. 4C is a perspective view of another embodiment for abutting thecovers;

FIG. 5 is a perspective view of the strainer basket being put in place;

FIG. 6 is a side view of the main sectional cover with the sensor probein place, partly broken away;

FIG. 7 is a schematic side view of the sensor probe circuit;

FIG. 8 is a perspective view of one half of an embodiment of the disk;

FIG. 9 is a perspective schematic view of a hopper and eductor useful inconnection with certain embodiments;

FIG. 10 is a front perspective view of an alternate shield;

FIG. 11 is a rear perspective view of the shield of FIG. 10;

FIG. 12 is an enlarged view of a portion of the shield of FIG. 10,partially disassembled;

FIGS. 13 and 14 are similar perspective views of an alternate wiringarrangement for the apparatus; and

FIG. 15 is a perspective view of a modified junction box usable with theapparatus for FIG. 14.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

In the following description, like reference characters designate likeor corresponding parts throughout the several figures. It should beunderstood that the illustrations are for the purpose of describingpreferred embodiments of the invention and are not intended to limit theinvention thereto.

As best seen in FIG. 1, the oil, grease and solid removal assembly 10includes a container 12 with sectional covers 14 a, 14 b, and 14 c. In apreferred embodiment as seen in FIG. 1, the sectional covers areseparate plates, preferably stainless steel. The assembly 10 has atleast one rotatable disk 16 (shown in FIG. 2) supported by the centersectional cover 14 b. FIG. 2 also depicts the gear drive motor 20 andthe trough 22 which are attached to the center sectional cover 14 b. Thecontainer 12 also includes an inlet pipe 26 and an outlet pipe 28. Theeffluent water with waste materials enters through the inlet pipe 26,and after oil, grease and solid waste have been removed, the grey waterexits out of the outlet pipe 28. As seen in FIG. 2, the trough 22 hasscraper blades 24. The gear drive motor 20 supports and rotates thedrive sprocket 38 which is cooperatively meshed with peripheral holes inthe disk 16.

The basket support 34 is depicted in FIG. 5. The basket support 34 isconstructed of rotomolded plastic and is designed to hold a strainerbasket 54. The basket support 34 is immediately downstream of the inletpipe 26 and has a cutout to align with the inlet pipe 26. Basket supportopenings 37 permits the effluent water with oil and grease to flowdownstream of the basket support 34 after the solid waste material hasbeen trapped in the strainer basket 54.

Referring to FIG. 1, the sectional covers 14 a, 14 b and 14 c cover eachof the sections of the oil, grease and solid waste removal assembly. Inthe preferred embodiment, a leading sectional cover 14 a provides easyaccess to the strainer basket 54 within the basket support 34 and adownward stream sectional cover 14 c is atop the outlet baffle (notshown) leading effluent from a low portion of the container 12 to theoutlet 28.

The center sectional cover 14 b is depicted in FIGS. 3 and 4. The centersectional cover 14 b is constructed of stainless steel and includes aflange 13 extending downwardly and laterally and a further extension 15,seen in FIG. 4. The rotatable disk 16 is constructed of oleophilicplastic or is at least covered with an oleophilic material. In oneembodiment, the disk 16 has equally spaced indentations 17 on its outercircumferential edge. The sprocket 38 meshes with the holes 17 in thedisk 16. The disk 16 is rotated clockwise in the view of FIG. 2 when thegear drive motor 20 rotates counter-clockwise.

As best seen in FIG. 2 the center sectional cover 14 b supports thetrough 22, which is constructed of stainless steel. The trough 22further includes elongated scraper blades 24 which are constructed of aflexible plastic or rubber material. As seen in FIG. 3, the centersectional cover 14 b also supports the heating element 50 which isutilized to maintain a sufficiently warm water temperature to melt anygrease contained in the grey water, permitting it to flow to and beremoved by the rotating disk 16. The heating element 50 seen in FIG. 2is a 300 watt heater with a quick reaction thermostat and is designed torun continuously. The timer 51 is connected to the gear drive motor 20and controls the start and stop operation of the gear drive motor 16 andultimately the rotation of the disk 16. It permits a selected duty cycleto remove grease at times when grease is likely to be present.

In the preferred embodiment, the oil, grease and solid removal assembly10 is connected to drain from a sink or other device that dischargeseffluent water with waste materials to be separated. The watercontaining waste materials flows from the device's drain into the oil,grease and solid removal assembly 10 through the inlet pipe 26. Theeffluent water flows into the basket support 34 containing a strainerbasket 54 and the solid waste materials are trapped and removed from theeffluent water. The effluent water containing oil and grease flowsdownstream from the basket support 34 through openings 37 into thecenter section. The center section cover 14 b supports the oil andgrease removal assembly. In the volume of the container 12 between thebasket support 34 and the outlet baffle 46, the effluent has time toreside, permitting oil and grease to rise to the top of the water. Thegrease is maintained in a liquid state by the heater 50. When the geardrive motor 20 turns the drive sprocket 38, the disk 16 is rotated in aclockwise direction by the counter clockwise rotation of the drivesprocket 38. The disk 16 is positioned in the center cover 14 b, so thatits lower portion is below the surface of the effluent water having theoil and grease which has floated to the surface. As the disk 16 rotatesthrough the water, oil and grease are picked up on the sides of the disk16. As the disk 16 rotates, the scraper blades 24 which are attached tothe trough 22 remove the oil and grease from the sides of the disk 16.The oil and grease flows down the trough 22 to an oil and grease storagecontainer (not shown). Once the oil and grease have been removed fromthe effluent water, the grey water flows downstream under the baffleoutlet and exits the oil, grease and solid removal assembly 10 throughthe outlet pipe 28 into the sewage system.

The oil, grease and solid removal assembly 10 is easy to maintain. Thecenter section cover 14 b containing the gear drive motor 20, the drivesprocket 38, the disk 16, the trough 22 and the scraper blades 24 is asingle, low cost unit. If there is a malfunction in any of thecomponents of this unit, it is more cost effective to replace the entireunit than to repair the malfunctioning component. By stocking an extraunit at the facility site, virtually no down time in operation of thelow cost oil, grease and solid removal assembly 10 would be experienced.In addition, because the center section cover 14 contains all of the oiland grease removal components, there is a greater flexibility in theinstallation process. The sectional cover 14 b can be installed to havethe trough 22 facing in opposite directions by placing the sectionalcover one way or the opposite way, depending on the needs of theinstallation. The sectional covers 14 a and 14 c are preferablyidentical and either can be positioned over the strainer basket or theoutlet baffle, depending on the selected orientation.

The container 12 of the low-cost oil, grease and solid removal assembly10 is constructed of a rotomolded plastic or welded stainless sheets.The container 12 is constructed with an inlet pipe 26 and the outletpipe 28. The sectional covers 14 can then be installed, although theymay well be removed and reinstalled at the jobsite.

Referring again to FIG. 1, the center sectional cover 14 b is providedwith a first shield 56 and a second shield 58. The shields are moldedplastic and are held in place over the trough component and electricalcomponents, respectively. By using separate shields over the twooperating components of the center sectional cover 14 b, humidity thatis generated through the openings around the rotating disk is segregatedfrom the electrical components shielded under the separate shield 58.The two shields 56 an 58 are each provided with hinged components. Ahinged component 60 lifts up to expose the rotating disk and trough, sothat debris clogging the trough and scraper blades can be removed. Thehinged cover 62 of the second shield 58 provides access to the timer 51so that adjustments can be made to the timer setting.

FIGS. 10-12 show an alternate shield embodiment. This embodiment stillhas two shields, but these are a front shield 156 and a rear shield 158.A hinged component 160 lifts up to expose the rotating disk and trough,so that debris clogging the trough and scraper blades can be removed.The hinged cover 162 provides access to the timer 51 so that adjustmentscan be made to the timer setting. Each of the shields 156, 159 hasinternal partitions that separate the volume under the shield into leftand right portions to keep humidity away from the electronics, as above.Preferably, the portion of the shield covering the disk has vents to lethumidity escape. The arrangement to join the front and rear shields andsimultaneously make a hinge barrel for the hinging covers 160 and 162 isseen in FIG. 12. The front shield has upwardly open half-cylinders 164,and the rear shield has downwardly open half-cylinders 166. Thehalf-cylinders are sized and shaped to form nearly complete cylinderswhen the rear shield and front shield are adjoined. Interposed betweenthe half cylinders are short cylindrical bosses 168 formed on ears ofthe covers 160 and 162. Edge guards 170 also help restrain the bosses toonly rotary motion within the nearly complete cylinders.

As seen in FIG. 1, the top sectional covers have edge mounted hooks 64.Clasp components 66 are positioned on the container 12, so that loops onthe clasps can hold the hooks 64 down in compressive relation to thecontainer 12. As seen in FIG. 3, the container 12 has an inwardly turnedupward flange 68 around the peripheral, capped by a gasket material 70so that as the sectional covers 14 a, 14 b, 14 c are held onto thecontainer, a seal is formed to prevent the egress of vapors from thecontainer 12. The mounting of additional sectional covers is shown inFIG. 4. The main sectional cover 14 b is provided with a downwardly andlaterally extending flange 13 with a downward extension 15. Thisdownward extension provides longitudinal rigidity to the sectional cover14 b.

As seen in FIG. 4, the additional cover 14 c is provided with anupwardly turned flange 72. Once the main sectional cover 14 b is inplace, the additional sectional cover 14 c can be mounted with theflange 72 overlying the downwardly and laterally extending flange 13. Agasket on the underside of the edge of the additional sectional cover 14c forms a seal with the top of the laterally and downwardly extendingflange 13. These seals need not be perfect.

As seen in FIG. 4A, for larger volume installations, a larger container12 can be used and multiple operative main sectional covers 14 b can beput in place with an intermediate additional cover 120, having oppositesides adapted to engage the main sectional covers 14 c. The oppositesides of the additional sectional cover 120 each have upper 122 andlower 124 protrusions spaced by a spacer 126 of a dimension, so that theupper protrusion 122 engages the upper surface of the flange 13 of themain sectional cover that extends downwardly and laterally, and thelower protrusion 124 engages the further downward extension 15 of themain sectional cover.

FIG. 4B shows an alternate embodiment of the additional cover 14 c inwhich a downward protrusion or flange 72 a is provided to abet thedownward extension 15 of the main sectional cover. A gasket 73 providesthe seal, which again need not be perfect.

FIG. 4C shows another alternative. In this embodiment, one of thesectional covers (the main sectional cover in this example) has slots75. Tabs 77 on the additional section are sized to fit into the slots toprovide a hinged but severable relationship between the sections. Thetabs and slots may be put on alternate ones of the sectional covers.

Referring now to FIG. 6, a sensor module 80 is shown mounted to the mainsectional cover 14 c. the sensor module 80 includes a probe 88 extendingdownwardly within the body of effluent water to a depth normally belowthe oil/grease. A sensor 90 within the probe provides electricalindications as to whether the sensor is in proximity to oil/grease orwater. Since the sensor 90 that is at a depth that normally is immersedin water, if the oil/grease mat floating on the water becomes unduelythick, because of a malfunction of the unit, the sensor 90 will detectthe change in the material in the proximity of the sensor. An alarm 86on the sensor module provides a human recognizable indication if thesensor senses that the probe is in proximity to oil/grease rather thannormally present water. The alarm 86 can be audible or a light, or othersuitable alarm indicator. A suitable sensor as is a capacitive sensorsuch as a K-1 Series Sensor available from IFM Electronic gmbH of Essen,Germany. The sensor 90 is held at the distal end of the probe 88 by aspacer 92 such as a block of foam material. The electrical circuitwithin the sensor module 80 is powered by a low voltage source 94. It isdesirable that the electrical power source be separate from the power tothe main separator unit, so that if the source of a malfunction is afailure of power to the entire assembly, it is less likely that thesensor probe will lose power. A remote monitoring output 96 can also beincluded in the sensor module and it is particularly desired to be ofthe type that provides connections to SCADA monitoring apparatuses.SCADA systems are well known facilities monitoring systems. A light 84is provided on the sensor module 80 to show that it is operating.

The electrical circuit of the sensor module is shown in FIG. 7.

A further improvement in the apparatus can be an improved form of thedisk 16, partially seen in respect to FIG. 8. FIG. 8 shows a disk sheet100 having spaced peripheral lugs 102 and radially inwardly positionedbosses 104. A central hole 106 is formed in this sheet and has asurrounding rim 106. Radially extending outward from the rim 106 are aplurality of ribs 108. The lugs 102 are preferably formed in an oddnumber of themselves and are equally spaced around the periphery of thedisk sheet 100. Two of the sheets 100 are made identically and joined tomake a complete disk. The side not shown in FIG. 8 is flat and isprovided with an oleophilic property. This property can be made bymaking the entire sheet 100 out of injection-molded plastic, preferablypolypropylene. By taking the two sheets and putting them together lugside-to-lug side rotated by a suitable amount, an equally spaced evennumber of peripheral teeth are provided in the combined disk. The bosses104 are provided equally spaced and permit alignment with holes 110 sothat screws can be passed through the holes 110 into the aligned bosses104 from both sides, forming a combined disk. The ribs 108 provideadditional rigidity to the disk, and during the molding process ribs 108permit the plastic to flow in the mold. The peripheral rim 106 providesa central bearing through which an axle may be passed, so that the diskcan rotate smoothly on the axle. Providing the disk in this fashionprovides a lower manufacturing cost than making a solid disk andmachining peripheral holes. In one embodiment, 29 lugs are provided oneach disk sheet, so that the combined sheets form a disk with 58peripheral lugs. The two sheets can also be joined by ultrasonic orvibration welding, passing screws, rather than bolts into the bosses, orany other suitable method. With this embodiment, the lugs form generallyaxially oriented flat surfaces which engage the sprocket. Therefore itis desirable to have square teeth on the drive sprocket to engage thelugs as the drive motor drives the disk, to make solid contact.

In a further embodiment, the strainer basket can be replaced with aneductor assembly 140. A hopper 142 is positioned in place of a strainerbasket and having a suitable overflow 144 for the grey water to exit thehopper 142. The hopper 142 has a converging downward configurationterminating in a narrowed portion 146 offset laterally from an eductor148 near the inlet end of the container. The eductor is offset laterallyfrom the bottom of the hopper, preferably, so that as solids collect atthe narrowed portion at the bottom of the hopper, they do not obstructthe eductor and inhibit its initiation of a jet. An inlet 150 to theeductor is provided with a water supply such as a municipal water supply(not shown). The water pressure from a narrowed inlet to an eductoroutlet forms a venturi jet effect to draw the solids from the bottom 146of the hopper through jet actuation. A tube 154 leads from the eductorto the outlet 28, passing the solids downstream. Preferably theapparatus is made so that it can be equipped either with the strainerassembly or the eductor assembly. The eductor assembly can beretrofitted to an installed system by removing the strainer andinstalling the hopper 142 with installed eductor 148, connecting a watersupply and connecting the tube 154 to the outlet 28. Eductors are knownin this art as shown in U.S. Pat. No. 6,491,830 and have proven to bevery effective in removing solids upstream of the oil/grease removaldisk assembly. The entire disclosure of that patent is herebyincorporated herein by reference.

Alternate power supply fittings can be seen in FIGS. 13-15. FIGS. 13 and14 show views of plug-in and hardwired arrangements respectively. Acustomer's choice of one version or another can be easily accommodatedby using one or the other of plates 170 or 172 with the components asdescribed herein when assembling the main sectional cover. Both platesare provided with covers 174 over possible future electrical orsignaling connections. The plate 170 of the embodiment of FIG. 13 isprovided with a line cord 176, enabling the apparatus to be plugged intoa wall socket. The plate 170 is secured to the remainder of the shieldby screws 178 passing through drilled and tapped holes 180. The plate172 of the embodiment of FIG. 14 is provided with a recessed male plug178. At the stage seen in FIG. 4, the plate 172 is unsecured to theremainder of the shield by although also drilled and tapped with holes180. As seen in FIG. 14, a junction box 181 is provided with aprotruding female plug 182 as well as a plate 186 that has holes 184positioned to align with holes 180 when the plugs 178 and 182 arejoined. At that stage, screws can be inserted to hold the plate andjunction box to the cover, securing the electrical connection against auser disconnecting power to the system. Those screws also hold the plate172 to the remainder of the shield. Of course, conduit and electricalwiring can be used in the junction box 181 in conventional fashion.

Certain modifications and improvements will occur to those skilled inthe art upon reading the foregoing description. It should be understoodthat all such modifications and improvements have been omitted for thesake of conciseness and readability, but are properly within the scopeof the following claims.

1.-41. (canceled)
 42. A method of assembly of a modular oil/grease removal assembly comprising: installing a container for receiving and holding effluent water containing oil/grease to be removed from the effluent water and having sectional covers; mounting a main sectional cover supporting a rotatable disk for partial immersion within effluent water in the container and in contact with the oil/grease, a drive in driving engagement to provide rotation of the disk when the drive is engaged; a trough mounted on the main sectional cover in engaging relation to opposite sides of the rotatable disk; a scraper blade mounted on the trough so that the scraper blade extends from the trough into sliding engagement with a side of the disk, the disk, scraper blade and trough cooperatively disposed and structured to direct oil and grease from the disk along the scraper blade along the trough for collection in a storage container and an electrical resistance heater that extends downwardly into the container so as to have an operable portion of the heater at least partially immersed within the body of effluent water to cause the oil/grease to be in liquid form, electrical controls for selectively operating the drive and the heater; mounting additional sectional covers to cover the container; and installing a first shield to cover the rotating disk, trough and scraper blade and a second shield to cover the electrical controls. 43.-47. (canceled)
 48. A method of assembly of a modular oil/grease removal assembly as claimed in claim 42 further comprising selecting a line cord or hard wired power input and installing the selected power input. 49-50. (canceled)
 51. A method of making a disk for a modular oil/grease removal assembly comprising forming two disk sheets separately and subsequently joining the two disk sheets together to form a disk.
 52. A method of making a disk for a modular oil/grease removal assembly as claimed in claim 51 wherein the two sheets are made identical and each include a flat oleophilic surface and a surface having a plurality of spaced peripheral lugs.
 53. A method of making a disk for a modular oil/grease removal assembly as claimed in claim 52 wherein the lugs of each sheet are odd in number including turning the oleophilic surfaces away from one another, interleaving the lugs of the opposing sheets, and joining the two sheets to form a periphery for the disk with gaps between the lugs.
 54. A method of making a disk for a modular oil/grease removal assembly as claimed in claim 51 wherein the sheets are joined by means selected from the group consisting of bolting, ultrasonic welding, vibration welding, other welding and adhering.
 55. A method of making a disk for a modular oil/grease removal assembly as claimed in claim 54 wherein the sheets have bosses on the same side as the lugs and joining the sheets at the bosses.
 56. A method of making a disk for a modular oil/grease removal assembly as claimed in claim 51 wherein forming the sheets is by injection molding plastic.
 57. A method of making a disk for a modular oil/grease removal assembly as claimed in claim 51 wherein forming the sheets is by injection molding polypropylene.
 58. A method of making a disk for a modular oil/grease removal assembly as claimed in claim 51 wherein forming includes forming the sheets with a central hole with a surrounding rim to form a bearing for an axle extending through the central hole.
 59. A method of assembly of a modular oil/grease removal assembly for receiving and holding effluent water containing oil/grease to be removed from the effluent water comprising: identifying an inlet source of effluent water and a downstream drain for grey water; installing a container having an inlet and an outlet; installing a main sectional cover that supports the functional apparatus to remove oil/grease from water and discharges oil/grease; mounting a sensor module to the main sectional cover including a probe extending downwardly within the body of effluent water to a depth normally below the oil/grease, a sensor in the probe providing electrical indications as to whether the sensor is in proximity to oil/grease or water, and an alarm on the sensor module to provide a human-recognizable indication if the sensor senses that the probe is in proximity to oil/grease rather than the normally-present water; and mounting additional sectional covers to completely cover the container.
 60. A method of assembly of a modular oil/grease removal assembly for receiving and holding effluent water containing oil/grease to be removed from the effluent water as claimed in claim 59 wherein the sensor and alarm are electrical and further comprising connecting a low voltage power supply to the sensor module that is separate from power to the functional apparatus to remove oil/grease from water.
 61. A method of assembly of a modular oil/grease removal assembly for receiving and holding effluent water containing oil/grease to be removed from the effluent water as claimed in claim 59 further comprising connecting an electrical alarm output from the sensor module to a remote monitoring apparatus to signal alarm conditions to the remote monitoring apparatus.
 62. A method of assembly of a modular oil/grease removal assembly for receiving and holding effluent water containing oil/grease to be removed from the effluent water as claimed in claim 61 wherein the monitoring apparatus is a SCADA monitoring apparatus.
 63. A method of assembly of a modular oil/grease removal assembly comprising: installing a container having an inlet at an inlet end for receiving and holding effluent water containing oil/grease to be removed from the effluent water and having sectional covers; mounting a main sectional cover supporting a rotatable disk for partial immersion within effluent water in the container and in contact with the oil/grease, a drive in driving engagement to provide rotation of the disk when the drive is engaged; a trough mounted on the main sectional cover in engaging relation to opposite sides of the rotatable disk; a scraper blade mounted on the trough so that the scraper blade extends from the trough into sliding engagement with a side of the disk, the disk, scraper blade and trough cooperatively disposed and structured to direct oil and grease from the disk along the scraper blade along the trough for collection in a storage container; mounting additional sectional covers to cover the container; and positioning a solids removal module at the inlet end.
 64. A method of assembly of a modular oil/grease removal assembly as claimed in claim 63 wherein the solids removal module is a strainer.
 65. A method of assembly of a modular oil/grease removal assembly as claimed in claim 63 wherein the solids removal module includes a hopper having an eductor at a lower portion of the hopper, and including connecting a water inlet to the eductor to make a jet of water to remove contents of the hopper in proximity to the eductor and connecting an outlet from the eductor to an outlet of the container.
 66. A method of modifying a modular oil/grease removal assembly having a container for receiving and holding effluent water containing oil/grease to be removed from the effluent water, a solids removal strainer, a main sectional cover that supports the functional apparatus to remove oil/grease from water and discharges oil/grease; and additional sectional covers comprising: removing one or more of the sectional covers; removing the solids removal strainer; and installing a hopper having an eductor at a lower portion of the hopper, and including connecting a water inlet to the eductor to make a jet of water to remove contents of the hopper in proximity to the eductor and connecting an outlet from the eductor to an outlet of the container. 67.-71. (canceled) 